1. Field of the Invention
The present invention relates to a LED (light-emitting diode) exposure head for use in a recording apparatus for linewise recording information on a moving photoreceptor.
2. Description of the Prior Art
A LED exposure head is known that comprises an assembly in alignment of a plurality of LED modules mounted on a common base, and an elongated lens array parallel to the row of LED's. The head is mounted in a rigid housing which allows the mounting of the head in the recording apparatus and which also offers protection of the optical and electronic components against harmful environmental conditions.
The housings of known exposure heads consist of two injection moulded light-alloy parts that closely fit together to form a closed housing. One part usually has a peripheral groove and the other one a peripheral lip which cooperate, occasionally with an appropriate sealant, to form an effective seal of the housing. Disadvantages of such housing are their expense and their outer dimensions, in particular their width. A reduced width of the housing is important, in particular in those instances where two or more color developments must be performed around the semiconductor drum of the recording apparatus. A color developing station requires quite considerable angular space around a semiconductor drum and this space is difficult to reduce.
It is easy to obtain a larger angular space for the different components by using a semiconductor drum of a large diameter, but this adds to the expense of size of the recording apparatus.